Top 5 Multi-Tenant Solar Billing Mistakes and How to Avoid Costly Errors

Now, more than ever, delivering accurate solar billing is critical—not just for regulatory compliance, but for building lasting trust with your tenants.

Solar billing, especially for multi-family properties, is more complex—and more costly—than ever before. If you’re a property owner or solar developer and feel overwhelmed or confused, you’re not alone. 

Across the country, the regulatory environment is evolving—rewriting the playbook for solar billing and credit allocation. In California, for example, the shift from NEM 2.0’s simple flat, retail-rate crediting to NEM 3.0’s dynamic, time-based compensation model has added new billing complexities. Even the smallest errors can quickly cascade into tenant disputes, regulatory headaches, and lost revenue. 

At Fram Energy, we’ve audited hundreds of solar billing statements—and we see the same costly mistake that, in the long-run, can quietly erode tenant trust and diminish the value of your solar investment.

Here are the 5 most common solar billing mistakes we see—and how to spot them before they impact your bottom line:

1. Mistakes in Manipulating Interval Data and Allocating Production kWh.

When it comes to multi-family solar billing, the devil is in the details. Those 15-minute interval snapshots drive the complex calculations for usage allocation and solar credit distribution across your tenant base. Even minor mistakes—like data formatting inconsistencies, incorrect time-stamping during daylight saving transitions, or missing readings due to system maintenance or national holidays—can compound into costly errors. 

Multi-family properties face an additional complexity. Common area loads, tenant turnover, and varying unit sizes all require precise data handling. Skip the details, and you risk more than just a miscalculation: billing errors can spark tenant disputes, erode trust, and lead to revenue losses and ongoing operational headaches. 

2. Mistakes in Applying Local Utility Billing and Crediting Logic.

Today’s solar compensation landscape features complex, utility-specific regulations that vary significantly across jurisdictions. We’re seeing states shift away from traditional net metering toward more complex, time-based compensation models that reflect the value of solar generation hour by hour. These new policies—like California’s Virtual Net Billing Tariff (V-NBT) and New York’s Value of Distributed Energy Resources (VDER)—bring their own crediting logic and reporting requirements. 

Many states have also transitioned from annual to monthly credit reconciliation, removing the “smoothing” effect that once helped balance out seasonal swings in production and usage. Instead of rolling over summer surpluses to offset winter consumption, tenants now see larger and less predictable fluctuations in their monthly bills—making it harder to track, understand, and trust their solar savings. 

The result? A far more complex, dynamic, and less predictable billing structure that varies across states and utility companies.

To get solar billing right, property managers and solar developers must remain vigilant—not only about compensation rates and credits, but also evolving consumer protection requirements and local utility policies that govern how solar benefits are distributed to tenants. 

3. Errors in the Bypassable and Non-Bypassable Rate Components.

Understanding the difference between bypassable and non-bypassable charges is crucial for accurate solar billing—yet, remains one of the most commonly misunderstood concepts of multi-family solar programs. Misapplying these charges can inflate savings projections and create significant gaps between expected and actual tenant benefits. 

• Bypassable Charges are fees directly tied to the amount of electricity consumed from the grid. These charges cover the cost of electricity generation, transmission, and distribution. When your on-site solar panels supply energy used in your building, you avoid these charges for the kilowatt-hours (kWh) produced and consumed behind-the-meter. 

• Non-Bypassable Charges are mandatory fees that cannot be offset by solar production or net metering credits. Tenants and property owners must pay for every kWh of electricity consumed from the grid. 

The complexity arises when billing systems incorrectly apply solar credits to non-bypassable portions of the bill, creating inflated savings projections that don’t materialize in actual tenant statements and can result in disappointed tenants and financial discrepancies.

4. Errors in Application of the Baseline Credit. 

The baseline allowance is a foundational element of tiered electricity billing, particularly in states like California. It defines the minimum kWh of electricity that regulators consider essential for basic living each month—billed at the lowest possible rate. Any usage above this baseline is charged at higher, progressively expensive tiers.

But applying the baseline allowance correctly is far from simple. It fluctuates based on location, primary heating source, season, the number of billing days, and whether residents qualify for medical baseline programs. All these variables form a complex, moving target that demands diligent tracking and frequent updates.

Common mistakes include relying on outdated baseline quantities, overlooking seasonal or geographic adjustments, misapplying medical allowances, or incorrectly calculating credits when solar production exceeds tenant consumption. Even minor missteps can cascade into larger problems: tenants may receive bills that overstate or understate their solar benefits, resulting in confusion, disputes, and—ultimately—a loss of trust and revenue for property owners.

5. Missing or Incorrect Application of CARE and Other Energy Assistance Discounts. 

Energy assistance programs—like California’s CARE and FERA or Texas’s LITE-UP—exist to help make electricity more affordable for eligible residents, especially low-income households. These programs can significantly reduce tenant electricity costs, often by 18-35%. Yet, in multi-family solar billing, these critical energy discounts are often missed, misapplied, or inconsistently administered. 

Property managers must stay on top of CARE eligibility tracking, enrollment / renewal deadlines, and ensure that both utility charges and solar credits are properly adjusted for the participating households’ discount rates. We commonly see billing errors such as missed enrollments, incorrect solar credit calculations, and improper discount stacking. 

These solar billing discrepancies can cost eligible tenants hundreds of dollars annually in lost utility bill savings they’re legally entitled to—undermining both tenant trust and putting your property at legal and regulatory risk.

Why Accurate Solar Billing Matters More Than Ever

These billing errors represent significant risks to tenant trust, regulatory compliance, and the overall financial performance of your solar investments. Even minor inaccuracies can snowball into tenant dissatisfaction, mounting administrative burdens, compliance headaches, and later reduced property value. 

That’s why at Fram Energy, we’ve developed a billing solution specifically designed to catch and correct these mistakes before they become costly problems. Our proprietary audit process combines advanced automated detection with expert human review to ensure every aspect of your solar billing is accurate and compliant—all the time.